Clearly, there is no magic source; one that always correctly indicates
which town an immigrant came from in the old country. The lack of such a
source makes this aspect of family history perhaps the most difficult, and
surely one of the most fascinating. Each source is valuable under different
circumstances.

The following factors all affect the value of any source for naming an
immigrant's home town:

How comprehensive the source was in listing immigrants

Time period of the source

Information the source recorded

Ethnic group of the immigrant

Religion of the immigrant

When the immigrant arrived

The age upon arrival of the immigrant

When the immigrant died (including how soon after arrival)

Gender of the immigrant

Other family members who immigrated

The key consideration as to which source to use depends on in which
time period the immigrant arrived. Some sources didn't even exist when
the earliest immigrants arrived in North America. Most sources changed
over time, usually adding more information, to the point that some eventually
required the inclusion of the home town. Some sources are better at
times simply because they have a better chance of including your immigrant.